<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="resource/js/vue.js"></script>
</head>
<body>
<div id="example">
    a={{a}}, b={{b}}
</div>

<script>
    var vm = new Vue({
        el: '#example',
        data: {
            a: 1
        },
        computed: {
            b: function(){
                return this.a + 1
            }
        }
    })
</script>
</body>
</html>